Commands by bw (6)

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Determine whether a CPU has 64 bit capability or not

synchronicity
The British Government entering in the Gregorian era.

Makefile argument passing
This would allow reference of $(VAR) (if defined) with the value 'foobar' within the Makefile.

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

pattern match in awk - no grep
Rather than chain a string of greps together and pipe them to awk, use awk to do all the work. In the above example, a string would be output to stdout if it matched pattern1 AND pattern2, but NOT pattern3.

Display the standard deviation of a column of numbers with awk
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.

Ultimate current directory usage command
An NCurses version of the famous old 'du' unix command

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Solaris - check ports/sockets which process has opened

Show max lengths of all fields in a pipe delimited file with header row


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